Phase Inverter Preference & Why?

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SilverFox
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Interstage Transformers

Post by SilverFox »

My understanding is they add harmonic content to the tone. I have a Trace Elliot Power amp that uses two, (it's stereo). The two output transformers are driven by Mosfet's. I've been told by a former Trace employee the output transformers were probably tube amp spec. I seem also to have heard that Bogner uses interstage coupling transformers in their designs.



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Leo_Gnardo
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Re: Phase Inverter Preference & Why?

Post by Leo_Gnardo »

jon wrote:Please elaborate I am very curious about inter-stage transformers.
Glad you're watching with respect to your PS160 style project. IIRC Fender didn't use any thumb-size interstage cobbed from a bass deficient Champ output, but a fairly chunky HiFi unit driven on the input by a 6V6. You might have a look at Edcor and what they offer. Some consider them difficult to deal with because they do no hand-holding with customers and build-to-order (they don't have a warehouse full of built transformers ready to sell) which sometimes means a wait of 2 months for delivery but their products are first rate and made in New Mexico, USA if that's a plus for you.

You may be able to find some more info & sources on IT's by scanning Audio Asylum. There's even an "inmate" there by the name . . . InterstageTranny. I'll bet he knows more than the average bear everything about IT's.
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jon
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Re: Phase Inverter Preference & Why?

Post by jon »

I've got the 160PS/300PS interstage audio transformer.
Smokebreak
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Re: Phase Inverter Preference & Why?

Post by Smokebreak »

The PI in my Gibson GA-95RVT is an interstage transformer, and that amp sounds great, after some circuit mods.:D I would bet there's no way even the corkiest of sniffers could hear it. Of course that's not to say it actually doesn't sound different than a cathodyne or LTP, etc
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Re: Phase Inverter Preference & Why?

Post by bb5000 »

My Weber AB200 has an interstage transformer driven by an EL34, the power amp is 6 x 6550.
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Leo_Gnardo
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Re: Phase Inverter Preference & Why?

Post by Leo_Gnardo »

jon wrote:I've got the 160PS/300PS interstage audio transformer.
D'OH! I knew that... In any case lots more IST info over there on AA. You needn't be a member to scan & search, and I think you can sign up at no cost should you want to get involved in the discussions. They'd prefer you pony up $25 a year or more, that gets you some privileges like listing items in their for-sale section. There is a wealth of information. And opinion. Enjoy!
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jjman
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Re: Phase Inverter Preference & Why?

Post by jjman »

I think interstage trannies "affect" the signal during clipping in a manner that tubes don't. Not sure of the technical difference nor if it sounds good or bad. Perhaps the "affect" cancels out when used as a PI.

I've never read anyone who said they are looking for that "clipping interstage tranny tone."
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